US2886967A

US2886967A - Pliability tester

Info

Publication number: US2886967A
Application number: US536850A
Authority: US
Inventors: John D Conti
Original assignee: American Viscose Corp
Current assignee: Akzo Nobel UK PLC
Priority date: 1955-09-27
Filing date: 1955-09-27
Publication date: 1959-05-19
Anticipated expiration: 1976-05-19

Description

ManyV 19, 1959 y J. D. CONTI 2,886,967

PLIABILITY TESTER J. D. CONTI PLIABILITY TESTER Many` 19, 1959 2 Sheets-Sheet 2 Filed Sept'. 2,7, 1955 WUnited States Patent() PLIABILITY TESTER John D. Conti, Elkins Park, Pa., assignor to American Viscose Corporation, Philadelphia, Pa., a corporation of Delaware Application September 27, 1955, Serial No. 536,850

11 Claims. (Cl. 7395) 'ditioning treatment designed to impart a desirable mois- 'ture content to the material. Conditioning is particularly important in the preparation of cellophane which has "undergone printing and has become somewhat brittle as Aa result of the drying stage during the printing procedure.

Conventionally, expensive and time consuming laboratorytechniques and skills have been hereto utilized for 'determining the moisture content of the materials, but this procedure is not suitable for mass production manufacture where numerous rapid and reliable control tests `are a requisite. More rapid moisture content tests have been made by comparison procedures based either on the weight or thickness of the material. In accordance fwith the present invention, the correlation existing between the moisture content of the material and its devgree of elongation or stretch during an interval of time and under controlled and weighted conditions is utilized. This latter method has provided quick and accurate results which conform with those obtained by laboratory testing, and it is therefore an object of this invention to provide a generally improved and more satisfactory apparatus for stretch or elongation studies of materials.

Another object is to provide an apparatus capable of subjecting all samples to the same test conditions and which is adjustable to vary the test conditions as desired. Still another object is the provision of test apparatus having a weighted beam which imparts an instantaneous stretching force to the test sample and which is locked in its weighted position at the termination of each test.

`A further object is to provide a test apparatus having ,a weighted beam which is associated with snubbing or dampening means enabling the beam to impart a con- `stant stretching force to the test sample and eliminating l.any tendency for the beam to move with a vibrating Vpendulum motion.

A still further object is the provision of a test apparatus which is simple in construction and operation, re- -quires little training and skill for use, and provides rapid and reliable results.

These and other objects and advantages of the inveni away;

Fig. 2 is a top view of the structure shown in Fig. l; Fig. 3 is a partial right side View of the apparatus as seen along the line 3-3 of Fig. l; i

the line 4--4 of Fig. 1;

- Fig. 4 is alongitudinal horizontal section taken along i l Fig. 5 is a transverse vertical section taken along the line 5-5 of Fig. 1 and Fig. 6 is a longitudinal horizontal section taken along the line 6-6 of Fig. 1.

In general, the invention relates to an elongation test apparatus for determining the moisture content of sheet materials on the basis of their stretch, and particularly to cellophane, when subjected to an instantaneous weight for a predetermined time period. The test sample is held between a fixed clamp and the end of the shorter arm of a beam pivoted inol-center relationship. The longer arm of the beam is weighted and is releasably held in an inoperative position by a latch .and a resilient brake, the latter of which is carried bythe beam and reacts upon a graduated arcuate segment relative to which the beam is movable during the test. Movement of the latch to an inoperative position concornitantly energizes a solenoid which in turn imparts a pivotal movement to the arcuate segment and thus permits the longer arm of the beam to instantaneously move to its weighted position while its shorter arm stretches the test sample. After a predetermined time interval, the solenoid is deenergized and the segment is resiliently urged into engagement with' the brake and the beam is thereby maintained in its weighted position to facilitate a reading of the graduated scale after the test is completed. A motion snubbing or dampening device is carried by the longer arm of the beam and includes a pawl which cooperates with the serrated edge of a fixed arcuate segment to prevent the beam from vibrating with a pendulum effect when first released, and thus prevents any tendency for the beam inertia from introducing errors in the results. The pawl arrangement also assists the brake in maintaining the graduated segment in its Weighted position.

With reference to the drawings, the test apparatus includes a support or standard 11 secured at its lower end, by bolts 13, to an angle iron 15, which in turn is welded or otherwise connected to a base plate 17. Pivoted at 19 to the upper end `of the standard 11 is a beam 21 having a short arm 23 and `a long arm 25, with a relative length ratio of approximately a 5 to 1. 'Depending from the end of the shorter arm 23 is a L-shaped member 27, the horizontal portion of which is provided with a V- shaped notch 29 within which the knife edge 31, extending between the bifurcated arms 33 of the sample clamp 35, is adapted to rest. The clamp 35 also includes a movable plate 37 which is adapted to be urged into gripping relationship with the upper portion of the test.` sample 39 by the screw 41 passing through the xed portion 43 of the clamp. The lower end of the sample 39 is secured in a similar clamp 45 having a movable plate 47 actuated by the screw 49 passing through the fixed portion 51 of the clamp. Bolts 53 secure the arm 55 of the clamp 45 to the horizontal flange 57 of the angle bracket 59. Preferably, the angle bracket is provided with vertically elongated slots 61 to facilitate adjustment thereof relative to the bolts 63 threaded into the standard 11. l

Secured at 65 to the longer arm 25 of the pivoted beam 21, is a cantilevered threaded rod 67 adjustably carrying weights 69. The outermost end of the arm 25 has a V-shaped notch 71 within which the knife edge 73, fixed to the end of` the `latch 75, is adapted to rest and thus maintains the beam 21 in its inoperative horizontal position shown in Fig. 1. The latch 'l5 is pivoted at '77 to the arm 79 connected by screws 81to the standard 11.

Fixed also to the arm 79, as by screws 83, is a conventional micro-switch having its resiliently urged contact pin 87 extending toward the adjacent end of the latch 75 for engagement therewith as hereinafter described.

aeeepe'r j i During the test procedure, the beam 21 pivots in a clockwise` direction, as viewed in Fig. l, with the outermost end of the arm 25 moving relative to a graduated arcuate segment 89 which is pivoted at 91 to the arm 79 and has its centeracoincident with that lof the pivot 19. The lower end of the segment $9 is continually urged yin `a countcrclockwise .direction by the spring 93 which has one end secured to the segment 89 by the hook 95 while its opposite end is xed to the lug 97 depending from the outer end of the Z-shaped support 99 ed at 101 to the standard 11. Secured also to the lower end of the segment 89, for purposes as hereafter described, is a cord or cable 193 which passes over the pulley 105, mounted on the support 99, and has its opposite end xed to the movable plunger 107 of a conventional solenoid 109. The solenoid 109 is supported by the standard 11 by means of the plate 111 and angle bracket 113.

To prevent the beam 21 from moving with a pendulum or vibrating motionwhen the latch 75 is released, a pawl 115 is rotatably carried by the beam 21 and is `resiliently urged, by the spring 123, into engagement with the serrations 1125 formed on the outer edge of the arcuate segment 127. The segment 127 is similar to segment 89 in that its center is coincident with that of the pivot 19 and is fixed to the arm 79 by the screw 91. However, in this case the lower end of the segment 127 is also xed by screw 129 to the arm 131 cantilevered from the standard 11 and connected at its outermost end to the support 99 through the spacer 133.

Reading of the graduated scale 135 on the face of the arcuate segment 89 is facilitated by the indicator 137 extending into the arm opening 139. Preferably, the scale 135 is calibratedr in moisture content units. The beam 21 is maintained in its weighted position after each test by means of a resilient brake 141, carried by the projection 143 on the beam itself, and is adapted to bear against the outermost periphery of the arcuate segment 89.

A timer unit 145, partially shown in Fig. 1, is electrically connected with the micro-switch 85'and the solenoid109 to permit variations in the time period to which the sample is subjected to the stretching load.

In testing, the sample 39 is first engaged at its upper end by the clamp 35 and is placed in a taut position by first removably securing a weight 147 to its lower end and then gripping the sample by the lower clamp 45. -It will be noted that the weight 147 permits each sample to be placed under the same degree of tension prior to actual testing. The weights 69 are then adjusted to the desired position and the latch 75 is rotated counterclock- Wise about its pivot 77, as viewed in Fig. 1, into engagement with the contact pin 87 of the micro-switch 85. Actuation of the micro-switch 85 electrically energizes the solenoid 109 through the timer 145, causing the lower end of the arcuate segment 89 to be drawn upwardly and to the left as viewed in Fig. l. In this manner, the segment S9 is released from contact with the resilient brake 141 and permits the weighted arm 25 of the beam 21 to instantaneously move clockwise, as viewed in Fig. 1, with its pawl 115 riding along the serrations 125 of the segment 127, preventing the beam 21 from moving with the pendulum or vibrating movement. At the desired time period, as determined by the pre-set adjustment of the timer 145, the solenoid 109 is deenergized allowing the spring 93 to draw the segment 89 into its normal or inoperative position against rthe brake 141 and thereby maintains the beam 21 in its weighted position. It will be noted that the beam 21 is maintained in its weighted position after the test has been completed thus making it unnecessary for the operator to read the scale 135 at the instant the testing time period is terminated.

The moisture control ofthe test sample 39 can be easily determined by observing the graduation on the scale 135 aligned with the indicator 137 of the beam 131.

While the description of the apparatus and test procedure has been `generally directed to testing a cellophane material, it is of course obvious that other similar materials can be equally well studied by the apparatus of the present invention. Further, it will be noted that the test procedure requires very little skill on the part of the operator insofar as the apparatus performs its operation automatically and in the desired sequence. Test conditions, such vas the weight to 'which the sample is subjected and the period of testing, can be readily varied as desired. However, `where cellophane bands or ribbons are undergoing testing, the sample is preferably subjected to a l5-second loading period, with the results thus obtained conforming accurately with those heretofore provided by the conventional laboratory testing procedure.

It is seen from the above description that the objects of the invention are well fulfilled by the structure described. The description is intended to be illustrative only and it is `to be understood that changes and variations may be made Without departing from the spirit and scope ofthe invention as defined by the appended claims.

I claim:

1. A test apparatus including means for maintaining a test material in taut position, means operatively connected with said first-mentioned means and adapted for movement to impart a stretching load to the test material, a graduated scale relative to which said last-mentioned means is movable for indicating the moisture content of the test material, and means operatively connected with said graduated scale for locking said movable means in a stationary position after the test material has been subjected to the stretching load for a predetermined time period.

2. A construction as defined in claim l wherein said means for imparting a vstretching load to the test material includes a pivotally mounted beam having a short arm Vconnected to said first-mentioned means and a weighted long arm providing the stretching load and being movable relative to said graduated scale.

3. A construction as defined in claim 2 wherein said long larm of said beam supports adjustable weights.

4. A construction as defined in claim 2 wherein said locking means includes a resilient brake carried by said long arm of said beam and adapted to engage with .said graduated scale.

5. A construction as defined in claim 2 wherein vsaid graduated scale is pivotally mounted and movable out of engagement with said long arm of said beam by means of a solenoid.

6. A construction as defined in claim 2 further including means for preventing said beam from moving witha vibratory motion when first released for pivotal ymovement.

7. A test apparatus including means for maintaining a test material in taut position, a pivotally mounted beam having a short arm connected with said means and `a weighted long arm adapted to impart a stretching load to the test material, an arcuate graduated scale pivoted at one end and having its center of curvature coincident with said beam pivot, releasable means for maintaining said graduated scale and beam in engagement to prevent pivotal movement of said beam, and means for pivotally moving said graduated segment out of engagement with said lon-g arm for a predetermined time period to permit said beam to pivot and impart a stretching load to said test material.

8. A construction as defined in claim 7 wherein said means for moving said graduated scale includes a solenoid operatively connected with and energized through a timer mechanism. v

9. A construction as dened in claim 8 further including a latch for holding said beam in inoperative position and a micro-switch operatively connected with said timer 5 mechanism and adapted to be energized as said latch is moved to release said beam.

10. A construction as defined in claim 7 further including a lixed arcuate segment, and means carried by Said long arm and adapted to engage with said fixed arcuate segment to prevent said beam from moving with a vibratory motion when irst released for pivotal movement.

l1. A test apparatus including means for supporting a test material in a taut position, movable means operatively connected with said supporting means for uniformly applying a known tensile load to the test material for a predetermined time period, means operatively connected with said movable means for indicating the degree of dis placement thereof during said predetermined time period,

and means for locking said movable means in its displaced 15 Cotton by R.

position at the end of the predetermined time period.

521,323 Schopper June 12, 1894 993,700 McKnight May 30, 1911 1,623,263 Nichols g Apr. 5, 1927 1,941,917 Schultz Jan. 2, 1934 FOREIGN PATENTS 858,32() Germany Dec. 4, 1952 OTHER REFERENCES Publication: Single Fiber Load Elongation Tester for S. Orr et al., Textile Research Journal, Vol. 23, No. 7, `l'uly 1953, pages 505-509.